Montero said there aren't many pitches in Hernandez's arsenal that are easy to handle.

"They're all tough, but the special one is the changeup," Montero said. "It goes down like a split. That's why he strikes out so many guys."

Hernandez (4-2) allowed five hits, walked none and struck out seven, improving to 3-0 with a 0.60 ERA in his past four starts.

"I've been aggressive, I've been throwing a lot of strikes and that's the key for me," Hernandez said.

Hernandez is 95-24 in his career when he receives two or more runs of support.

"He's special," Seager said. "He goes about his business. You give him a couple of runs and you know he's going to take care of the rest."

Seager had three hits in helping the Mariners win for the sixth time in eight games.

"He's been very consistent," manager Eric Wedge said of Seager. "He does a lot of things right."

Tom Wilhelmsen pitched the ninth for the Mariners, who had lost seven of their previous eight road games.

Hernandez came in 3-4 with a 5.13 ERA in nine career starts against the Blue Jays, easily his highest ERA against any opponent he's faced more than once, and had allowed seven runs in his previous two meetings with Toronto. But the right-hander was dominant in this one, allowing just two hits, an infield chopper and a bloop single, through the first six innings.

Adam Lind doubled to begin the eighth and went to third on Colby Rasmus' single. But Rasmus was doubled off first when Maicer Izturis lined out and Munenori Kawasaki grounded out.

"That was big, that was real big," Hernandez said of the double play.

Shut out for the third time this season, the struggling Blue Jays lost for the seventh time in eight games and fell a season-high 10 games below .500.

Making his first start of the season, Blue Jays left-hander Ricky Romero (0-1) allowed three runs and three hits in four innings. He walked three and struck out four.

Romero started in place of right-hander Josh Johnson, who is on the disabled list with triceps soreness.

An All-Star in 2011, Romero went 9-14 with a 5.77 ERA and an AL-worst 105 walks in 32 starts last season, then was demoted to the minors at the end of spring training this year to work on his mechanics. After spending time at extended spring training, Romero made one start for Class A Dunedin last week, allowing one run in seven innings.

Romero looked sharp early against Seattle. He faced the minimum through the first three innings, striking out three and throwing just 33 pitches.

He struggled in the fourth, however, as the Mariners batted around and scored three runs on two hits and three walks.

"At the beginning of the game I thought he was dynamite," Gibbons said. "I know he's a little disappointed in that, but I think it's a good starting point."

Michael Saunders walked to begin the fourth and Seager crushed the next pitch into the second deck in right, his fourth homer of the season.

Kendrys Morales was hit by a pitch and advanced on a wild pitch before Gibbons and assistant trainer Mike Frostad came out to check on Romero, who said he had a callus on his left hand.

Michael Morse struck out looking, but walks to Bay and Justin Smoak loaded the bases for Dustin Ackley, who grounded an RBI single through the right side.

Montero followed with a one-hopper that struck Romero on the left forearm, but he recovered to flip home for the force out. Gibbons and Frostad came out again to check on Romero, who stayed in and got Brendan Ryan to pop out.

"I just lost control of where the fastball was going," Romero said. "Almost seemed like I was spiking it."

Romero's arm stiffened after the inning and he was removed. X-rays were negative and he is day to day.

Bay hit an opposite field shot to right off Aaron Loup in the sixth, his third.

"That's a great sign when you see a right-hander drive the ball the other way like he did," Wedge said.

NOTES: Toronto's Jose Bautista played his 1,000th career game. ... Daren Brown joined the Mariners to serve as third base coach in place of Jeff Datz, who is battling cancer. Brown had been managing Triple-A Tacoma. Minor league catching coordinator John Stearns, who'd been filling in for Datz, will replace Brown at Tacoma. ... Blue Jays OF Melky Cabrera, who had batted sixth the previous two games, moved back to the second spot in the order, with Lind dropping to sixth.